Guild housing could be easily be implemented using the existing mission system. Have a special guild mission booth where a Guild leader can go and get an empty mission. He can duplicate the key and give to guild members. Make the mission zone %25 suppression gas. Have an /org command to delete all Guild house keys in the event of a total breach of security.

This would make Guild battles a reality. You could have an Agent sneak into an opposing guild house after “acquiring” a copy of the current guild house key and assassinate the guild leader! If there is a contract out on a guild member, someone can be hired to assassinate that character. Maybe have an Agent hiding in a corner of the guild house waiting for their assassination target to come in. Or have an Enforcer bust in and start busting heads for wholesale slaughter. Or perhaps a bureaucrat or fixer running in rooting everyone and then the rest of the team come in and clean up. With a doctor and a trader in the team you can have some very interesting skirmishes, especially if you have an NT using AoE nukes!